Use your Windows password for the screen saver password
You can help make your computer more secure by creating a screen saver password, which locks your computer when the screen saver is on. The screen saver password is the same password that you use to log on to Windows.
Open Screen Saver Settings by clicking the Start button , and then clicking Control Panel. In the search box, type screen saver, and then click Set screen saver password.
Select the On resume, display logon screen check box, set a time when you want the screen saver to start, and then click OK. (Choose a time that's not long enough for an unauthorized person to use your computer, but not so short that if you stop working at your computer, the screen saver locks it.)